Quantitative evaluation method of power supply reliability considering voltage sag

Based on the analysis of the original quantitative evaluation system of power supply reliability, aiming at the influence of voltage sag on industrial users, a hierarchical quantitative evaluation system of power supply reliability considering voltage sag is proposed. The new index system aims to evaluate the reliability of the impact of voltage sag from the perspective of the structure, function and safety of industrial users. The specific evaluation methods are mainly composed of direct loss evaluation, indirect loss evaluation and potential safety hazard evaluation. Direct loss refers to the economic loss caused by the interruption of industrial process after the occurrence of voltage sag. Indirect loss refers to the economic loss caused by defective products due to the imperfect industrial production process. The potential safety hazard refers to the potential safety hazard of the production line where the important equipment is located after suffering voltage sag. This paper focuses on the rationality of quantitative evaluation with the principle of economic equivalence, the significance and internal relations of industrial user structure, function and safety index, and puts forward a reasonable calculation method. Through the case calculation, the layered evaluation results are consistent with the empirical conclusions, with applicability.